A plurality of circuit patterns (or photoresist patterns) may be mostly formed on a wafer using a photolithography process. In particular, with a reduction in the design rule of semiconductor devices, more attention may be paid to the importance of the critical-dimension (CD) uniformity of circuit patterns.
Although the CD uniformity of the circuit patterns may be affected by optical factors, such as a light source, lens, and aperture of an exposure apparatus, the CD uniformity of circuit patterns of a highly integrated semiconductor device may be affected by the CD of mask patterns of a photomask. Thus, to increase the CD uniformity of the circuit patterns formed on a wafer, the CD uniformity of the mask patterns of the photomask may be increased.
To increase the CD uniformity of the mask patterns, the CD of the photomask may be corrected. For example, when the mask patterns have a large CD, a predetermined treatment should be performed on the photomask to reduce the CD of the mask patterns.
Also, the CD uniformity of the circuit patterns may be affected by a process parameter of a semiconductor fabrication process, for example, a development process. To improve the CD uniformity of the circuit patterns, the process parameter of the development process may be controlled. The CD of the mask patterns may also be corrected. However, such correction may benefit by improved global CD uniformity and local CD uniformity.